After setting up all the Product Type fields and Product Types, we can setup categories. Here we can specify for each category which product types are allowed for upload.
Plus it has multi-language support, of course, and the Description, Visibility, Availability fields will let admins to configure the categories properly.
Here’s how the Products Category manager looks like (it will be available only for the marketplace admins):
Update: We’ve recorded a video so you can see all these in action: